package ai.zixing.mashibing.basic_class.class11;

public class Code0_F {
    public static void main(String[] args) {
        System.out.println(f(6));
    }

    public static int f(int n) {
        if (n == 1 || n == 2) {
            return 1;
        }
        return f(n - 1) + f(n - 2);
    }

}
